POS1503 LONGITUDINAL STUDY OF PREGNANCY OUTCOMES IN INDIGENOUS VERSUS NON-INDIGENOUS LUPUS PATIENTS IN WESTERN AUSTRALIA
Authors: J. Nossent, C. Inderjeeth, D. Preen, H. Keen
Journal: Annals of the Rheumatic Diseases (2023)

<h3>Background</h3> Ethnicity remains a key determinant of outcome in SLE and Indigenous Australian patients (IA) are disproportionately affected in term of renal failure and mortality <sup>[1,2]</sup>. Pregnancy in SLE patients associates with maternal and foetal morbidity, but there is no data on pregnancy in IA SLE patients. <h3>Objectives</h3> To compare pregnancy outcomes and complications between IA and non-IA (NI) patients with SLE over three decades between 1985-2015. <h3>Methods</h3> Using state-wide hospital morbidity data, we compared rates for live birth (LB), abortive outcome (AO), preterm birth and gestational complications across pregnancies in IA (n = 31) and non-Indigenous (NI) SLE patients (n = 357) in Western Australia over a thirty-year period. Results presented are medians compared by Kruskal-Wallis test and proportions with odds ratios (ORs) (95% CI) compared by χ2 testing across groups and study decades. <h3>Results</h3> A total of 702 SLE pregnancies were recorded (62 in IA and 640 in NI). Median age at first pregnancy was significantly lower in IA (27 years, IQR 20-32) than NI patients (30 years, IQR 26-34) (p&lt;0.001), with no difference in median number of pregnancies (2 vs 2, OR 1.1 CI 0.56-2.4). Over the whole study period, LB rate was similar for IA and NI patients (74.2 % vs 72.8, OR p=0.45); however, LB rate increased from 65.5 to 79.6% in NI patients over time (p=0.01) and decreased from 88.9 to 75.9 in IA patients (p=0.34). In NI patients, the proportion of caesarean births was stable over time (35.5 to 37.7%, p= 0.56) but decreased in IA patients (44.4 to 20.7%, p=0.24). Preterm birth occurred in 10.3 % of live births in NI and 9.7 % of IA patients (OR 1.14, CI 0.49-3.10, p = 0.82) with the proportion of preterm deliveries increasing over time in both groups (from 0 to 10.3% in IA and from 4.9 to 7.9% in NA). A single case of congenital heart block occurred (prevalence 0.15%). Gestational diabetes (16.1 vs 2.4 %), infections 12.4 vs 4.1%) and renal disease (22.6 vs 4%) complicated more pregnancies in IA patients (all p&lt;0.001) and showed increasing rates over the three study decades, while these rates remained stable in NI patients except for an increase in diabetes (1.3 to 5.1%). <h3>Conclusion</h3> While LB rates have increased in NI lupus patients over time, they decreased in IA patients in association with an increase in comorbid complications. This suggest that stricter monitoring of pregnancy in IA lupus patients is required to achieve the level of improvement observed in NI lupus patients, that is in line with current literature data <sup>[3]</sup>. <h3>References</h3> [1] Petri M. Pregnancy and Systemic Lupus Erythematosus. Best Practice &amp; Research Clinical Obstetrics and Gynaecology 64 (2020) 24-30. [2] J Nossent et al. The current role for clinical and renal histological findings as predictor for outcome in Australian patients with lupus nephritis. Lupus 2018 Oct;27(11):1838-1846. [3] Braga A et al. Systemic Lupus Erythematosus and Pregnancy: a PortugueseCase–Control Study. Clinical Reviews in Allergy &amp; Immunology (2022) 62:324–332. <h3>Acknowledgements:</h3> NIL. <h3>Disclosure of Interests</h3> None Declared.